/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
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 *
 *
 *
 *
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 *
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 *
 *
 *
 */

package javax.swing.plaf.metal;

import java.awt.event.*;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import javax.swing.plaf.*;
import javax.swing.plaf.basic.*;
import java.awt.*;
import java.io.*;
import java.security.*;

/**
 * Provides the metal look and feel implementation of <code>RootPaneUI</code>.
 * <p>
 * <code>MetalRootPaneUI</code> provides support for the
 * <code>windowDecorationStyle</code> property of <code>JRootPane</code>.
 * <code>MetalRootPaneUI</code> does this by way of installing a custom
 * <code>LayoutManager</code>, a private <code>Component</code> to render
 * the appropriate widgets, and a private <code>Border</code>. The
 * <code>LayoutManager</code> is always installed, regardless of the value of
 * the <code>windowDecorationStyle</code> property, but the
 * <code>Border</code> and <code>Component</code> are only installed/added if
 * the <code>windowDecorationStyle</code> is other than
 * <code>JRootPane.NONE</code>.
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Terry Kellerman
 * @since 1.4
 */
public class MetalRootPaneUI extends BasicRootPaneUI {

  /**
   * Keys to lookup borders in defaults table.
   */
  private static final String[] borderKeys = new String[]{
      null, "RootPane.frameBorder", "RootPane.plainDialogBorder",
      "RootPane.informationDialogBorder",
      "RootPane.errorDialogBorder", "RootPane.colorChooserDialogBorder",
      "RootPane.fileChooserDialogBorder", "RootPane.questionDialogBorder",
      "RootPane.warningDialogBorder"
  };
  /**
   * The amount of space (in pixels) that the cursor is changed on.
   */
  private static final int CORNER_DRAG_WIDTH = 16;

  /**
   * Region from edges that dragging is active from.
   */
  private static final int BORDER_DRAG_THICKNESS = 5;

  /**
   * Window the <code>JRootPane</code> is in.
   */
  private Window window;

  /**
   * <code>JComponent</code> providing window decorations. This will be
   * null if not providing window decorations.
   */
  private JComponent titlePane;

  /**
   * <code>MouseInputListener</code> that is added to the parent
   * <code>Window</code> the <code>JRootPane</code> is contained in.
   */
  private MouseInputListener mouseInputListener;

  /**
   * The <code>LayoutManager</code> that is set on the
   * <code>JRootPane</code>.
   */
  private LayoutManager layoutManager;

  /**
   * <code>LayoutManager</code> of the <code>JRootPane</code> before we
   * replaced it.
   */
  private LayoutManager savedOldLayout;

  /**
   * <code>JRootPane</code> providing the look and feel for.
   */
  private JRootPane root;

  /**
   * <code>Cursor</code> used to track the cursor set by the user.
   * This is initially <code>Cursor.DEFAULT_CURSOR</code>.
   */
  private Cursor lastCursor =
      Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR);

  /**
   * Creates a UI for a <code>JRootPane</code>.
   *
   * @param c the JRootPane the RootPaneUI will be created for
   * @return the RootPaneUI implementation for the passed in JRootPane
   */
  public static ComponentUI createUI(JComponent c) {
    return new MetalRootPaneUI();
  }

  /**
   * Invokes supers implementation of <code>installUI</code> to install
   * the necessary state onto the passed in <code>JRootPane</code>
   * to render the metal look and feel implementation of
   * <code>RootPaneUI</code>. If
   * the <code>windowDecorationStyle</code> property of the
   * <code>JRootPane</code> is other than <code>JRootPane.NONE</code>,
   * this will add a custom <code>Component</code> to render the widgets to
   * <code>JRootPane</code>, as well as installing a custom
   * <code>Border</code> and <code>LayoutManager</code> on the
   * <code>JRootPane</code>.
   *
   * @param c the JRootPane to install state onto
   */
  public void installUI(JComponent c) {
    super.installUI(c);
    root = (JRootPane) c;
    int style = root.getWindowDecorationStyle();
    if (style != JRootPane.NONE) {
      installClientDecorations(root);
    }
  }


  /**
   * Invokes supers implementation to uninstall any of its state. This will
   * also reset the <code>LayoutManager</code> of the <code>JRootPane</code>.
   * If a <code>Component</code> has been added to the <code>JRootPane</code>
   * to render the window decoration style, this method will remove it.
   * Similarly, this will revert the Border and LayoutManager of the
   * <code>JRootPane</code> to what it was before <code>installUI</code>
   * was invoked.
   *
   * @param c the JRootPane to uninstall state from
   */
  public void uninstallUI(JComponent c) {
    super.uninstallUI(c);
    uninstallClientDecorations(root);

    layoutManager = null;
    mouseInputListener = null;
    root = null;
  }

  /**
   * Installs the appropriate <code>Border</code> onto the
   * <code>JRootPane</code>.
   */
  void installBorder(JRootPane root) {
    int style = root.getWindowDecorationStyle();

    if (style == JRootPane.NONE) {
      LookAndFeel.uninstallBorder(root);
    } else {
      LookAndFeel.installBorder(root, borderKeys[style]);
    }
  }

  /**
   * Removes any border that may have been installed.
   */
  private void uninstallBorder(JRootPane root) {
    LookAndFeel.uninstallBorder(root);
  }

  /**
   * Installs the necessary Listeners on the parent <code>Window</code>,
   * if there is one.
   * <p>
   * This takes the parent so that cleanup can be done from
   * <code>removeNotify</code>, at which point the parent hasn't been
   * reset yet.
   *
   * @param parent The parent of the JRootPane
   */
  private void installWindowListeners(JRootPane root, Component parent) {
    if (parent instanceof Window) {
      window = (Window) parent;
    } else {
      window = SwingUtilities.getWindowAncestor(parent);
    }
    if (window != null) {
      if (mouseInputListener == null) {
        mouseInputListener = createWindowMouseInputListener(root);
      }
      window.addMouseListener(mouseInputListener);
      window.addMouseMotionListener(mouseInputListener);
    }
  }

  /**
   * Uninstalls the necessary Listeners on the <code>Window</code> the
   * Listeners were last installed on.
   */
  private void uninstallWindowListeners(JRootPane root) {
    if (window != null) {
      window.removeMouseListener(mouseInputListener);
      window.removeMouseMotionListener(mouseInputListener);
    }
  }

  /**
   * Installs the appropriate LayoutManager on the <code>JRootPane</code>
   * to render the window decorations.
   */
  private void installLayout(JRootPane root) {
    if (layoutManager == null) {
      layoutManager = createLayoutManager();
    }
    savedOldLayout = root.getLayout();
    root.setLayout(layoutManager);
  }

  /**
   * Uninstalls the previously installed <code>LayoutManager</code>.
   */
  private void uninstallLayout(JRootPane root) {
    if (savedOldLayout != null) {
      root.setLayout(savedOldLayout);
      savedOldLayout = null;
    }
  }

  /**
   * Installs the necessary state onto the JRootPane to render client
   * decorations. This is ONLY invoked if the <code>JRootPane</code>
   * has a decoration style other than <code>JRootPane.NONE</code>.
   */
  private void installClientDecorations(JRootPane root) {
    installBorder(root);

    JComponent titlePane = createTitlePane(root);

    setTitlePane(root, titlePane);
    installWindowListeners(root, root.getParent());
    installLayout(root);
    if (window != null) {
      root.revalidate();
      root.repaint();
    }
  }

  /**
   * Uninstalls any state that <code>installClientDecorations</code> has
   * installed.
   * <p>
   * NOTE: This may be called if you haven't installed client decorations
   * yet (ie before <code>installClientDecorations</code> has been invoked).
   */
  private void uninstallClientDecorations(JRootPane root) {
    uninstallBorder(root);
    uninstallWindowListeners(root);
    setTitlePane(root, null);
    uninstallLayout(root);
    // We have to revalidate/repaint root if the style is JRootPane.NONE
    // only. When we needs to call revalidate/repaint with other styles
    // the installClientDecorations is always called after this method
    // imediatly and it will cause the revalidate/repaint at the proper
    // time.
    int style = root.getWindowDecorationStyle();
    if (style == JRootPane.NONE) {
      root.repaint();
      root.revalidate();
    }
    // Reset the cursor, as we may have changed it to a resize cursor
    if (window != null) {
      window.setCursor(Cursor.getPredefinedCursor
          (Cursor.DEFAULT_CURSOR));
    }
    window = null;
  }

  /**
   * Returns the <code>JComponent</code> to render the window decoration
   * style.
   */
  private JComponent createTitlePane(JRootPane root) {
    return new MetalTitlePane(root, this);
  }

  /**
   * Returns a <code>MouseListener</code> that will be added to the
   * <code>Window</code> containing the <code>JRootPane</code>.
   */
  private MouseInputListener createWindowMouseInputListener(JRootPane root) {
    return new MouseInputHandler();
  }

  /**
   * Returns a <code>LayoutManager</code> that will be set on the
   * <code>JRootPane</code>.
   */
  private LayoutManager createLayoutManager() {
    return new MetalRootLayout();
  }

  /**
   * Sets the window title pane -- the JComponent used to provide a plaf a
   * way to override the native operating system's window title pane with
   * one whose look and feel are controlled by the plaf.  The plaf creates
   * and sets this value; the default is null, implying a native operating
   * system window title pane.
   *
   * @param content the <code>JComponent</code> to use for the window title pane.
   */
  private void setTitlePane(JRootPane root, JComponent titlePane) {
    JLayeredPane layeredPane = root.getLayeredPane();
    JComponent oldTitlePane = getTitlePane();

    if (oldTitlePane != null) {
      oldTitlePane.setVisible(false);
      layeredPane.remove(oldTitlePane);
    }
    if (titlePane != null) {
      layeredPane.add(titlePane, JLayeredPane.FRAME_CONTENT_LAYER);
      titlePane.setVisible(true);
    }
    this.titlePane = titlePane;
  }

  /**
   * Returns the <code>JComponent</code> rendering the title pane. If this
   * returns null, it implies there is no need to render window decorations.
   *
   * @return the current window title pane, or null
   * @see #setTitlePane
   */
  private JComponent getTitlePane() {
    return titlePane;
  }

  /**
   * Returns the <code>JRootPane</code> we're providing the look and
   * feel for.
   */
  private JRootPane getRootPane() {
    return root;
  }

  /**
   * Invoked when a property changes. <code>MetalRootPaneUI</code> is
   * primarily interested in events originating from the
   * <code>JRootPane</code> it has been installed on identifying the
   * property <code>windowDecorationStyle</code>. If the
   * <code>windowDecorationStyle</code> has changed to a value other
   * than <code>JRootPane.NONE</code>, this will add a <code>Component</code>
   * to the <code>JRootPane</code> to render the window decorations, as well
   * as installing a <code>Border</code> on the <code>JRootPane</code>.
   * On the other hand, if the <code>windowDecorationStyle</code> has
   * changed to <code>JRootPane.NONE</code>, this will remove the
   * <code>Component</code> that has been added to the <code>JRootPane</code>
   * as well resetting the Border to what it was before
   * <code>installUI</code> was invoked.
   *
   * @param e A PropertyChangeEvent object describing the event source and the property that has
   * changed.
   */
  public void propertyChange(PropertyChangeEvent e) {
    super.propertyChange(e);

    String propertyName = e.getPropertyName();
    if (propertyName == null) {
      return;
    }

    if (propertyName.equals("windowDecorationStyle")) {
      JRootPane root = (JRootPane) e.getSource();
      int style = root.getWindowDecorationStyle();

      // This is potentially more than needs to be done,
      // but it rarely happens and makes the install/uninstall process
      // simpler. MetalTitlePane also assumes it will be recreated if
      // the decoration style changes.
      uninstallClientDecorations(root);
      if (style != JRootPane.NONE) {
        installClientDecorations(root);
      }
    } else if (propertyName.equals("ancestor")) {
      uninstallWindowListeners(root);
      if (((JRootPane) e.getSource()).getWindowDecorationStyle() !=
          JRootPane.NONE) {
        installWindowListeners(root, root.getParent());
      }
    }
    return;
  }

  /**
   * A custom layout manager that is responsible for the layout of
   * layeredPane, glassPane, menuBar and titlePane, if one has been
   * installed.
   */
  // NOTE: Ideally this would extends JRootPane.RootLayout, but that
  //       would force this to be non-static.
  private static class MetalRootLayout implements LayoutManager2 {

    /**
     * Returns the amount of space the layout would like to have.
     *
     * @param the Container for which this layout manager is being used
     * @return a Dimension object containing the layout's preferred size
     */
    public Dimension preferredLayoutSize(Container parent) {
      Dimension cpd, mbd, tpd;
      int cpWidth = 0;
      int cpHeight = 0;
      int mbWidth = 0;
      int mbHeight = 0;
      int tpWidth = 0;
      int tpHeight = 0;
      Insets i = parent.getInsets();
      JRootPane root = (JRootPane) parent;

      if (root.getContentPane() != null) {
        cpd = root.getContentPane().getPreferredSize();
      } else {
        cpd = root.getSize();
      }
      if (cpd != null) {
        cpWidth = cpd.width;
        cpHeight = cpd.height;
      }

      if (root.getMenuBar() != null) {
        mbd = root.getMenuBar().getPreferredSize();
        if (mbd != null) {
          mbWidth = mbd.width;
          mbHeight = mbd.height;
        }
      }

      if (root.getWindowDecorationStyle() != JRootPane.NONE &&
          (root.getUI() instanceof MetalRootPaneUI)) {
        JComponent titlePane = ((MetalRootPaneUI) root.getUI()).
            getTitlePane();
        if (titlePane != null) {
          tpd = titlePane.getPreferredSize();
          if (tpd != null) {
            tpWidth = tpd.width;
            tpHeight = tpd.height;
          }
        }
      }

      return new Dimension(Math.max(Math.max(cpWidth, mbWidth), tpWidth) + i.left + i.right,
          cpHeight + mbHeight + tpWidth + i.top + i.bottom);
    }

    /**
     * Returns the minimum amount of space the layout needs.
     *
     * @param the Container for which this layout manager is being used
     * @return a Dimension object containing the layout's minimum size
     */
    public Dimension minimumLayoutSize(Container parent) {
      Dimension cpd, mbd, tpd;
      int cpWidth = 0;
      int cpHeight = 0;
      int mbWidth = 0;
      int mbHeight = 0;
      int tpWidth = 0;
      int tpHeight = 0;
      Insets i = parent.getInsets();
      JRootPane root = (JRootPane) parent;

      if (root.getContentPane() != null) {
        cpd = root.getContentPane().getMinimumSize();
      } else {
        cpd = root.getSize();
      }
      if (cpd != null) {
        cpWidth = cpd.width;
        cpHeight = cpd.height;
      }

      if (root.getMenuBar() != null) {
        mbd = root.getMenuBar().getMinimumSize();
        if (mbd != null) {
          mbWidth = mbd.width;
          mbHeight = mbd.height;
        }
      }
      if (root.getWindowDecorationStyle() != JRootPane.NONE &&
          (root.getUI() instanceof MetalRootPaneUI)) {
        JComponent titlePane = ((MetalRootPaneUI) root.getUI()).
            getTitlePane();
        if (titlePane != null) {
          tpd = titlePane.getMinimumSize();
          if (tpd != null) {
            tpWidth = tpd.width;
            tpHeight = tpd.height;
          }
        }
      }

      return new Dimension(Math.max(Math.max(cpWidth, mbWidth), tpWidth) + i.left + i.right,
          cpHeight + mbHeight + tpWidth + i.top + i.bottom);
    }

    /**
     * Returns the maximum amount of space the layout can use.
     *
     * @param the Container for which this layout manager is being used
     * @return a Dimension object containing the layout's maximum size
     */
    public Dimension maximumLayoutSize(Container target) {
      Dimension cpd, mbd, tpd;
      int cpWidth = Integer.MAX_VALUE;
      int cpHeight = Integer.MAX_VALUE;
      int mbWidth = Integer.MAX_VALUE;
      int mbHeight = Integer.MAX_VALUE;
      int tpWidth = Integer.MAX_VALUE;
      int tpHeight = Integer.MAX_VALUE;
      Insets i = target.getInsets();
      JRootPane root = (JRootPane) target;

      if (root.getContentPane() != null) {
        cpd = root.getContentPane().getMaximumSize();
        if (cpd != null) {
          cpWidth = cpd.width;
          cpHeight = cpd.height;
        }
      }

      if (root.getMenuBar() != null) {
        mbd = root.getMenuBar().getMaximumSize();
        if (mbd != null) {
          mbWidth = mbd.width;
          mbHeight = mbd.height;
        }
      }

      if (root.getWindowDecorationStyle() != JRootPane.NONE &&
          (root.getUI() instanceof MetalRootPaneUI)) {
        JComponent titlePane = ((MetalRootPaneUI) root.getUI()).
            getTitlePane();
        if (titlePane != null) {
          tpd = titlePane.getMaximumSize();
          if (tpd != null) {
            tpWidth = tpd.width;
            tpHeight = tpd.height;
          }
        }
      }

      int maxHeight = Math.max(Math.max(cpHeight, mbHeight), tpHeight);
      // Only overflows if 3 real non-MAX_VALUE heights, sum to > MAX_VALUE
      // Only will happen if sums to more than 2 billion units.  Not likely.
      if (maxHeight != Integer.MAX_VALUE) {
        maxHeight = cpHeight + mbHeight + tpHeight + i.top + i.bottom;
      }

      int maxWidth = Math.max(Math.max(cpWidth, mbWidth), tpWidth);
      // Similar overflow comment as above
      if (maxWidth != Integer.MAX_VALUE) {
        maxWidth += i.left + i.right;
      }

      return new Dimension(maxWidth, maxHeight);
    }

    /**
     * Instructs the layout manager to perform the layout for the specified
     * container.
     *
     * @param the Container for which this layout manager is being used
     */
    public void layoutContainer(Container parent) {
      JRootPane root = (JRootPane) parent;
      Rectangle b = root.getBounds();
      Insets i = root.getInsets();
      int nextY = 0;
      int w = b.width - i.right - i.left;
      int h = b.height - i.top - i.bottom;

      if (root.getLayeredPane() != null) {
        root.getLayeredPane().setBounds(i.left, i.top, w, h);
      }
      if (root.getGlassPane() != null) {
        root.getGlassPane().setBounds(i.left, i.top, w, h);
      }
      // Note: This is laying out the children in the layeredPane,
      // technically, these are not our children.
      if (root.getWindowDecorationStyle() != JRootPane.NONE &&
          (root.getUI() instanceof MetalRootPaneUI)) {
        JComponent titlePane = ((MetalRootPaneUI) root.getUI()).
            getTitlePane();
        if (titlePane != null) {
          Dimension tpd = titlePane.getPreferredSize();
          if (tpd != null) {
            int tpHeight = tpd.height;
            titlePane.setBounds(0, 0, w, tpHeight);
            nextY += tpHeight;
          }
        }
      }
      if (root.getMenuBar() != null) {
        Dimension mbd = root.getMenuBar().getPreferredSize();
        root.getMenuBar().setBounds(0, nextY, w, mbd.height);
        nextY += mbd.height;
      }
      if (root.getContentPane() != null) {
        Dimension cpd = root.getContentPane().getPreferredSize();
        root.getContentPane().setBounds(0, nextY, w,
            h < nextY ? 0 : h - nextY);
      }
    }

    public void addLayoutComponent(String name, Component comp) {
    }

    public void removeLayoutComponent(Component comp) {
    }

    public void addLayoutComponent(Component comp, Object constraints) {
    }

    public float getLayoutAlignmentX(Container target) {
      return 0.0f;
    }

    public float getLayoutAlignmentY(Container target) {
      return 0.0f;
    }

    public void invalidateLayout(Container target) {
    }
  }


  /**
   * Maps from positions to cursor type. Refer to calculateCorner and
   * calculatePosition for details of this.
   */
  private static final int[] cursorMapping = new int[]
      {Cursor.NW_RESIZE_CURSOR, Cursor.NW_RESIZE_CURSOR, Cursor.N_RESIZE_CURSOR,
          Cursor.NE_RESIZE_CURSOR, Cursor.NE_RESIZE_CURSOR,
          Cursor.NW_RESIZE_CURSOR, 0, 0, 0, Cursor.NE_RESIZE_CURSOR,
          Cursor.W_RESIZE_CURSOR, 0, 0, 0, Cursor.E_RESIZE_CURSOR,
          Cursor.SW_RESIZE_CURSOR, 0, 0, 0, Cursor.SE_RESIZE_CURSOR,
          Cursor.SW_RESIZE_CURSOR, Cursor.SW_RESIZE_CURSOR, Cursor.S_RESIZE_CURSOR,
          Cursor.SE_RESIZE_CURSOR, Cursor.SE_RESIZE_CURSOR
      };

  /**
   * MouseInputHandler is responsible for handling resize/moving of
   * the Window. It sets the cursor directly on the Window when then
   * mouse moves over a hot spot.
   */
  private class MouseInputHandler implements MouseInputListener {

    /**
     * Set to true if the drag operation is moving the window.
     */
    private boolean isMovingWindow;

    /**
     * Used to determine the corner the resize is occurring from.
     */
    private int dragCursor;

    /**
     * X location the mouse went down on for a drag operation.
     */
    private int dragOffsetX;

    /**
     * Y location the mouse went down on for a drag operation.
     */
    private int dragOffsetY;

    /**
     * Width of the window when the drag started.
     */
    private int dragWidth;

    /**
     * Height of the window when the drag started.
     */
    private int dragHeight;

    public void mousePressed(MouseEvent ev) {
      JRootPane rootPane = getRootPane();

      if (rootPane.getWindowDecorationStyle() == JRootPane.NONE) {
        return;
      }
      Point dragWindowOffset = ev.getPoint();
      Window w = (Window) ev.getSource();
      if (w != null) {
        w.toFront();
      }
      Point convertedDragWindowOffset = SwingUtilities.convertPoint(
          w, dragWindowOffset, getTitlePane());

      Frame f = null;
      Dialog d = null;

      if (w instanceof Frame) {
        f = (Frame) w;
      } else if (w instanceof Dialog) {
        d = (Dialog) w;
      }

      int frameState = (f != null) ? f.getExtendedState() : 0;

      if (getTitlePane() != null &&
          getTitlePane().contains(convertedDragWindowOffset)) {
        if ((f != null && ((frameState & Frame.MAXIMIZED_BOTH) == 0)
            || (d != null))
            && dragWindowOffset.y >= BORDER_DRAG_THICKNESS
            && dragWindowOffset.x >= BORDER_DRAG_THICKNESS
            && dragWindowOffset.x < w.getWidth()
            - BORDER_DRAG_THICKNESS) {
          isMovingWindow = true;
          dragOffsetX = dragWindowOffset.x;
          dragOffsetY = dragWindowOffset.y;
        }
      } else if (f != null && f.isResizable()
          && ((frameState & Frame.MAXIMIZED_BOTH) == 0)
          || (d != null && d.isResizable())) {
        dragOffsetX = dragWindowOffset.x;
        dragOffsetY = dragWindowOffset.y;
        dragWidth = w.getWidth();
        dragHeight = w.getHeight();
        dragCursor = getCursor(calculateCorner(
            w, dragWindowOffset.x, dragWindowOffset.y));
      }
    }

    public void mouseReleased(MouseEvent ev) {
      if (dragCursor != 0 && window != null && !window.isValid()) {
        // Some Window systems validate as you resize, others won't,
        // thus the check for validity before repainting.
        window.validate();
        getRootPane().repaint();
      }
      isMovingWindow = false;
      dragCursor = 0;
    }

    public void mouseMoved(MouseEvent ev) {
      JRootPane root = getRootPane();

      if (root.getWindowDecorationStyle() == JRootPane.NONE) {
        return;
      }

      Window w = (Window) ev.getSource();

      Frame f = null;
      Dialog d = null;

      if (w instanceof Frame) {
        f = (Frame) w;
      } else if (w instanceof Dialog) {
        d = (Dialog) w;
      }

      // Update the cursor
      int cursor = getCursor(calculateCorner(w, ev.getX(), ev.getY()));

      if (cursor != 0 && ((f != null && (f.isResizable() &&
          (f.getExtendedState() & Frame.MAXIMIZED_BOTH) == 0))
          || (d != null && d.isResizable()))) {
        w.setCursor(Cursor.getPredefinedCursor(cursor));
      } else {
        w.setCursor(lastCursor);
      }
    }

    private void adjust(Rectangle bounds, Dimension min, int deltaX,
        int deltaY, int deltaWidth, int deltaHeight) {
      bounds.x += deltaX;
      bounds.y += deltaY;
      bounds.width += deltaWidth;
      bounds.height += deltaHeight;
      if (min != null) {
        if (bounds.width < min.width) {
          int correction = min.width - bounds.width;
          if (deltaX != 0) {
            bounds.x -= correction;
          }
          bounds.width = min.width;
        }
        if (bounds.height < min.height) {
          int correction = min.height - bounds.height;
          if (deltaY != 0) {
            bounds.y -= correction;
          }
          bounds.height = min.height;
        }
      }
    }

    public void mouseDragged(MouseEvent ev) {
      Window w = (Window) ev.getSource();
      Point pt = ev.getPoint();

      if (isMovingWindow) {
        Point eventLocationOnScreen = ev.getLocationOnScreen();
        w.setLocation(eventLocationOnScreen.x - dragOffsetX,
            eventLocationOnScreen.y - dragOffsetY);
      } else if (dragCursor != 0) {
        Rectangle r = w.getBounds();
        Rectangle startBounds = new Rectangle(r);
        Dimension min = w.getMinimumSize();

        switch (dragCursor) {
          case Cursor.E_RESIZE_CURSOR:
            adjust(r, min, 0, 0, pt.x + (dragWidth - dragOffsetX) -
                r.width, 0);
            break;
          case Cursor.S_RESIZE_CURSOR:
            adjust(r, min, 0, 0, 0, pt.y + (dragHeight - dragOffsetY) -
                r.height);
            break;
          case Cursor.N_RESIZE_CURSOR:
            adjust(r, min, 0, pt.y - dragOffsetY, 0,
                -(pt.y - dragOffsetY));
            break;
          case Cursor.W_RESIZE_CURSOR:
            adjust(r, min, pt.x - dragOffsetX, 0,
                -(pt.x - dragOffsetX), 0);
            break;
          case Cursor.NE_RESIZE_CURSOR:
            adjust(r, min, 0, pt.y - dragOffsetY,
                pt.x + (dragWidth - dragOffsetX) - r.width,
                -(pt.y - dragOffsetY));
            break;
          case Cursor.SE_RESIZE_CURSOR:
            adjust(r, min, 0, 0,
                pt.x + (dragWidth - dragOffsetX) - r.width,
                pt.y + (dragHeight - dragOffsetY) -
                    r.height);
            break;
          case Cursor.NW_RESIZE_CURSOR:
            adjust(r, min, pt.x - dragOffsetX,
                pt.y - dragOffsetY,
                -(pt.x - dragOffsetX),
                -(pt.y - dragOffsetY));
            break;
          case Cursor.SW_RESIZE_CURSOR:
            adjust(r, min, pt.x - dragOffsetX, 0,
                -(pt.x - dragOffsetX),
                pt.y + (dragHeight - dragOffsetY) - r.height);
            break;
          default:
            break;
        }
        if (!r.equals(startBounds)) {
          w.setBounds(r);
          // Defer repaint/validate on mouseReleased unless dynamic
          // layout is active.
          if (Toolkit.getDefaultToolkit().isDynamicLayoutActive()) {
            w.validate();
            getRootPane().repaint();
          }
        }
      }
    }

    public void mouseEntered(MouseEvent ev) {
      Window w = (Window) ev.getSource();
      lastCursor = w.getCursor();
      mouseMoved(ev);
    }

    public void mouseExited(MouseEvent ev) {
      Window w = (Window) ev.getSource();
      w.setCursor(lastCursor);
    }

    public void mouseClicked(MouseEvent ev) {
      Window w = (Window) ev.getSource();
      Frame f = null;

      if (w instanceof Frame) {
        f = (Frame) w;
      } else {
        return;
      }

      Point convertedPoint = SwingUtilities.convertPoint(
          w, ev.getPoint(), getTitlePane());

      int state = f.getExtendedState();
      if (getTitlePane() != null &&
          getTitlePane().contains(convertedPoint)) {
        if ((ev.getClickCount() % 2) == 0 &&
            ((ev.getModifiers() & InputEvent.BUTTON1_MASK) != 0)) {
          if (f.isResizable()) {
            if ((state & Frame.MAXIMIZED_BOTH) != 0) {
              f.setExtendedState(state & ~Frame.MAXIMIZED_BOTH);
            } else {
              f.setExtendedState(state | Frame.MAXIMIZED_BOTH);
            }
            return;
          }
        }
      }
    }

    /**
     * Returns the corner that contains the point <code>x</code>,
     * <code>y</code>, or -1 if the position doesn't match a corner.
     */
    private int calculateCorner(Window w, int x, int y) {
      Insets insets = w.getInsets();
      int xPosition = calculatePosition(x - insets.left,
          w.getWidth() - insets.left - insets.right);
      int yPosition = calculatePosition(y - insets.top,
          w.getHeight() - insets.top - insets.bottom);

      if (xPosition == -1 || yPosition == -1) {
        return -1;
      }
      return yPosition * 5 + xPosition;
    }

    /**
     * Returns the Cursor to render for the specified corner. This returns
     * 0 if the corner doesn't map to a valid Cursor
     */
    private int getCursor(int corner) {
      if (corner == -1) {
        return 0;
      }
      return cursorMapping[corner];
    }

    /**
     * Returns an integer indicating the position of <code>spot</code>
     * in <code>width</code>. The return value will be:
     * 0 if < BORDER_DRAG_THICKNESS
     * 1 if < CORNER_DRAG_WIDTH
     * 2 if >= CORNER_DRAG_WIDTH && < width - BORDER_DRAG_THICKNESS
     * 3 if >= width - CORNER_DRAG_WIDTH
     * 4 if >= width - BORDER_DRAG_THICKNESS
     * 5 otherwise
     */
    private int calculatePosition(int spot, int width) {
      if (spot < BORDER_DRAG_THICKNESS) {
        return 0;
      }
      if (spot < CORNER_DRAG_WIDTH) {
        return 1;
      }
      if (spot >= (width - BORDER_DRAG_THICKNESS)) {
        return 4;
      }
      if (spot >= (width - CORNER_DRAG_WIDTH)) {
        return 3;
      }
      return 2;
    }
  }
}
